Switch lock



July 16, 1929. c. cHdRl-STENSEN SWITCH LOCK Filed Aug. 8. 1923 2 Sheets-Sheet 1 MII..

July 15, 1929. c.V cHRls'n-:NSEN 1,720.818

SWITCH LOCK n Filed Aug. 8, 1923 2 Sheets-Sheet 2 @I gym.

Patented July 16, 1929".

UNITED STATES PATENT OFFICE.

CHRISTEN CHRISTENSEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO ELECTRICAL ENGI- NEERS EQUIPMENT COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F ILLI- N OIS.

SWITCH LOCK.

Application filed August 8, 1923. Serial No. 656,442.

The present invention relates to electrical switches and particularly to improvements in locking mechanism therefor.

In high tension switches, or switches designed for outdoor installation, it is a common practice to mount the pivot terminal, which pivotally supports the switch blade, on one insulator, and to mount the other terminal, with which the blade contacts, on another insulator spaced from the first insulator, and both projecting from a common mounting base. These two insulators carry substantially the entire weight of the switch, and receive the stresses set u in the switch by its operation, and possiblgy some additional stresses transmitted from the line to the switch. Where these insulators are relatively high for handling high voltages, they are often subject to considerable deliection or displacement under the above weight and stresses, and this frequently displaces the terminals to such an extent as to bind or prevent the operation of the switch lock mechanism.

It is the fundamental object of the present invention to provide a switch lock which will remain positive and reliable in operation even under a relatively large deflection of the insulators and switch terminals. One structural feature b which this object is attained, is to have the lock mechanism engage over a longitudinal edge of the blade, whereby the blade can shift longitudinally throughout a substantially unlimited range without disengaging from the lock mechanism or otherwise interfering with the normal operation of the lock.

Another structural feature, tending toward the foregoing object, is the arrangement whereby the blade and locking jaws are guided together laterally in order to offset lateral deflections of the insulators or terminals.

Referring to the accompanying drawings wherein I haveillustrated a preferred embodiment of my invention Fig. 1 is a side elevational View of a switch embodying my invention, the central part of the switch being broken away;

Fig. 2 is an enlarged transverse sectional view taken on the plane of the line 2-2 of Fig. 1;

Fig. 3 is a longitudinal sectional view taken on the plane of the line 3-'3 of Fig. 2;

Fig. 4 is a side elevational view of a slightly modified form;

Fig. is a transverse sectional View 0f a modified form of locking mechanism; and

Fig. G is a longtudinal sectional view taken approximately on the plane of the line 6 6 of Fig. 5.

The switch is erected upon an conventional form of base or supporting frame 8 which can be mounted on the pole top, switching tower, or in any other desired location. Rising from this base are two insulators 9 and 11, the upper end of the former carrying the hinge terminal 12, to which the switch blade 13 is pivoted, and the upper end of the latter carrying the contact terminal 14. Each terminal has extending therefrom a connecting lug or clip 15, to which are connected the opposite sides of the line 16.

The switch blade 13 comprises two spaced blades 13 engaging on o posite sides of the hinge terminal 12. t? pivot bolt V17 passes through these switch blades and through the hinge terminal, having sprin washers 18 engaging under each bolt head and normally urging the switch blades into firm. contact with the sides of the terminal 12. The other end of the blade unit carries a ring 19 extending out beyond the end of the blade unit, the eye in this ring forming a convenient grasping means for engagement by an operating pole having a hook end adapted to engage therein.

Extending upwardly on each side of the contact terminal 14 is a guiding horn 21, the throat 22 between which horns substantially coincides with the kupper end of the contact terminal 14 so as to guide the two switch blades 13-13 down on opposite sides of this terminal. Each guiding horn 21 comprises a rear orouter wall 23 and two forwardly extending side walls 24 which form vertical rectangular recesses 25 in the opposing faces of the guiding horn for receiving the detent members 26.A Extending upwardly fr om the recess portion 25 yis a curved hornconsisting of a front web 27 having reinforcing ribs or flanges 28 extending backwardly along each edge of the web 27.

As shown in Fig. 2, the upper part of the contact terminal 14 is reduced in thickness to form slots on each side between the terminal and opposing faces of the guiding horn 21, the switch blades 13-13 being r',- ceivable in the slots. The scarfed-out sides of the terminal leave shoulders 29 which form positive stops for the inward movement of the switch blades 13. The thicker portion below the shoulder 29 is formed with a horizontal base 31 adapted to be attached to the terminal bracket or head 32 carried on the upper end of the insulator 11. The lower ends of the guiding horn 21 are placed in substantial contact with the sides of the widened terminal portion, and these horns are each formed with a cross web or bar 33 for bolting to the terminal base 31. This web or bar 33 is provided with a bolt hole .through which passes a bolt 34, the latter extending down through an aligned hole in the terminal base 31 and tappiirg` into the mounting head 32 on the top of the insulator. The outer walls 23 of the horns are y cut away, as indicatedV at 35 to provide openings for manipulating the bolt-s 34 in securing the contact terminal and guiding horns to the mounting member 32.

The detent Vor locking function' is performed by the two members which are mounted for pivotal motion in the rectangular recesses or pockets he upper ends of these detent members 26 have inwardly extending jaws 36 which are adapted to hook over the upper longitudinal edges of the blades 13.

From the jaws 36, the detent members are curved backwardly to form guiding horns 37 by which the switch blades 13 are guided over the terminal 14 and the detent members 26 are cammed apart for permitting this engagement of the switch blades over the terminal. The detent members 26 are pivotally supported at their lower ends by providing pivot pins or studs 38 extending from each edge of the detent member in the plane parallel to the switch blades. These pivot studs repose in arcuate slots 39 cut in the under sides of the guiding horns.

Each detent `member 26 is preferably urged against. its respective blade member 13 by suitable spring mechanism, whereby an intimate firm contact is maintained between the blade 13 and-terminal 14, and also between the blade and the detent member 26. This spring mechanism may consist of springs arranged singly or in duplicate to apply a resilient pressure to the back of each detent member at one or more points. 1n the arrangement shown, any upper spring 41 bears against the back of each detent member adjacent the upper edge of the switch blade, having its end confined around a stud 42 projecting from the back of the detent member. The other end of the spring is centered on an adjustable screw 43 threading through the wall 23 of the horn. By threading this screw 43 in or out, any desired pressure may be imposed on the detent member 26 for restraining the switch blade in position over the contact terminal 14. Vhen two springs are employed for pressing the detent member 26 against its corresponding switch blade, the second spring is preferably arranged to bear against the detent member 26 at a point adjacent the lower edge of the switch blade so as to distribute the spring pressure of the two springs across the entire width of the blade. Such a second spring is illustrated at 45 in Fig. 2, this spring bearing at its inner end against a centering stud 46 projecting from the back of the member 26. This spring may be of adjustable pressure through the medium of an adjusting screw 43, or may be of iiXed pressure, asdesired. For illustrating an alternative arrangement I have shown the spring as being of fixed pressure, and in this case the outer end of the spring takes into a cupped recess 47 formed in the outer wall 23 ofthe guiding horn. The upper spring 41 may similarly be of fixed pressure setting by having its end seated in the upper cupped recess 47 and dispensing with the screw 43.

It will be observed that by locating the two jaws 26 in the same transverse plane as the cont-act terminal 14, and by applying spring pressure to the outer sides of these jaws acting inwardly against the switch blades, these jaws perform the secondary function of firmly pressing the switch blades into intimate contact with the contact terminal for effective electrical connection, in addition to their function of lockng or restraining the switch blades. A uniform application of the spring pressure across the width of the switch blade is secured by providing a slight amount of play between the pivot studs 33 and the arcuate slots 3,9 in which they are confined, This lateral play allows each detent member 26 to have a lateral translational motion whereby the spring pressure is operative'to shift the detent member into firm pressure contact with the switch blade across its entire width. This spacing between the pivot stud and its bearing recess 39 is indicated at 40.

The aws or detent members 26may operate as a friction or spring lock, or as a positive lock, depending upon the requirements of the situation.

There a spring lock is desired, the surfaces 36 are sloped at an angle, substantially as shown in Fig. 2, so that a sharp outward jerk on the switch blade is operative to cam the locking members 26 apart and permit the switch blades to be drawn out over the end of the contact terminal 14. Thercstraint offered by these surfaces 3G to opening movement of the switch blade can be widely varied by changing the angle of these surfaces 86, and by threading the adjusting screws 43 in or out to increase or decrease the pressure on the outer ends of the locking members 2G. Thus by changing the slope of the surface 3G to a very abrupt wedge and increasing the pressure ol' the cooperating spring 41:1 Ythe restraint opposed to opening mot-ion of the switch may be made to closely approach that or' a positive lock. lVhen a positive lock is desired, means must be provided for releasing this positive lock before the switch blade can be withdrawn. An exemplary form ot means is illustrated in Figs. 5 and G. As shown in Fig. (3, it will be noted that the detent surfaces 3G are cut at right angles to the locking aws to hook over the outer edges of the switch blades 13- and positively lock these switch blades in against the contacting terminal. The jaw members 2G are separated by a lock releasing member 51 which is pivoted on a. pivot pin 52 extending through the switch blades 13 adjacent their outer ends. A pivot lug 53 extends down from the releasing member 51 between the switch blades, and receives the pivot pin 52. A ring 511 extends from the outer end of the switch releasing member 5l for receiving the hook on the end of the operating pole. The inner end of the lock releasing member is curved down between the guiding horns 2l and carries arblocl; or separating member 55 at its lower end This separating member is adapted to be forced down between the curved horns 37 on the upper ends of the jaws 26, whereby the jaws are cammed apart and the locking shoulders 36 are forced to the sides of the switch blades for permitting' the latter to be withdrawn. This will follow as a natural sequence resulting from an upward or outward pull exerted on the ring 54; through the switch operating pole. The initial effort will force the separating bleek 55 down between the curved horns 87, so as to separate the locking jaws, attr which the continued pull on the pole will draw the switch blades out over the end ot' the contact terminal 14.

lVhile I have shown and described my invention in particular detail it will be apparent that various and many modifications may be made without depart-ing from the scope of my invention.

I claim l. In a switch lock, the combination of a switch terminal, a pair of guiding horns its pressure contact across the entire width of said blade.

3. In a switch lock the combination ot' a switch terminal, a detent member, a switch blade movable between said detent member an( said switch terminal, a pivotal mounting ior the lower end of said detent member, spring means normally urging said detent member against said switch blade, said pivotal mounting permitting a slight translational motion of the lower end of said detent member.

4. In a switch, the combination of a switch terminal, a pair of guide members rising from opposite sides of said switch terminal, a disconnect element comprising a pair of switch blades engageable upon opposite sides of said terminal, a locking jaw pivotally connected to each of said guiding members, a spring tending to move said locking jaw towards said switch terminal, and means carried by said guide members for adjusting the pressure of said spring.

5. In a switch, the combination of a switch terminal having a base member, a. pair of guiding horns, one rising on each side of said switch terminal, bolts securing said guiding horns to the base portion of said switch terminal, a pair of locking jaws between said switch terminal and said guiding horns, each of said locking jaws having pivot studs extending theretrom and engaging in bearing slots, a cam surface on the upper end of each of said locking jaws, a locking surface on the inner side of each of said locking jaws engageable over the edge of the corresponding switch blade, and spring means between each of said locking jaws and the adjacent guiding horn.

6. In combination, a terminal, a` blade for contacting the said terminal, a locking element for locking the blade in engagement with the terminal and resilient means acting in a plane substantially at right angles to that of the blade for urging the locking e-lement into tight engagement with the blade to'cause the blade to be pressed into firm contact with the terminal.

7. In combinaion, a switch terminal, a floating switch element including a pair of blades adapted t0 be moved into engagement with the said terminal, means for guiding the movement of the blades into engagement with the terminal, means for locking the blades in engagement with the terminal, and independent resilient means positioned intermediate the guiding means and the locking means for urging the locking means into engagement with the terminal.

8. In combination, a contact member, a locking member having free movement toward and away from the contact member, a switch blade operating` between said members in Contact therewith, and yielding means urging the locking member toward the blade and holding it fiat against the blade.

9. In combination, a contact member, a locking member having rectilineal movement toward and away from the contact member, a switch blade operating` between said members in contact therewith, and yielding means urging the lockingmember toward the blade.

l0. In combination, a contact member, a locking member movable toward and away from the contact member, a. switch blade operating between said members in contact therewith, and yielding means urging the locking member toward the blade, said locking member fitting fiat against the blade and firmly contacting therewith throughout the width of the blade.

l1. In combination, a contact member, 'a blade having an opening receiving said member, the blade contacting with the lateral faces of the contact member, locking members at opposite sides of the contact member and movable toward and away from the same, and yielding means urging the locking members toward the contact member, said locking members contacting with the lateral faces of the blade and exerting pressure thereon holding the blade in contact with the lateral faces of the contact member.

l2. In combination, a contact member, a blade having an opening receiving said member, the blade contacting with the lateral faces of the contact member, locking members at opposite sides of the contact member and movable toward and away from the same, and yielding means urging the locking members toward the contact member, said locking members contacting with the lateral faces of the blade throughout the width thereof and exerting pressure thereon holding the blade in contact with the lateral faces of the contact member.

13. In combination, a contact member, a blade having an opening receiving said member, the blade contacting with the lateral faces of the contact member, locking members at opposite sides of the contact member, said locking members being loosely mounted for rocking and rectilineal movement toward and away from the contact member, and yielding means urging the locking members toward the contact member and into contact with the lateral faces of the blade.

In witness whereof, I hereunto subscribe my name this 30th day of July, 1923.

CHRISTEN CHRISTENSEN. 

